I. Field of the Invention
Drums are containers used to store and transport many different types of contents. Drums can be constructed of one of many types of material. Generally though, drums are made of metal. Typical drum sizes are 30 gallon and 55 gallon. Due to stresses imposed on the drums, either externally during transport and storage or internally from pressurized contents or heavy contents, drums need to be rigid and strong. Typical types of materials that are stored in drums include: oil, starches, glues, paints, ethylene glycols, fatty acids, flavorings and essential oils. Drum bottoms require strength as well as stability for standing upright.
A common problem in the drum art is that drum contents always remains in the bottom of the container. The inability to recover all of the drum contents results in wasted product and increased costs as well as possible toxic problems or spoilage problems. In addition, drums are often reused, but because they cannot be easily and fully emptied, the drums require complete emptying and then cleaning in order for reuse. There is a need in the container related art for an improved drum bottom that provides increased recovery of drum contents and thus, a drum bottom that is more efficient and economical.
The present invention relates to containers or drums and is directed particularly to a type of drum bottom. This field of art is always looking for ways to recover more contents from a drum container. The present invention relates to an improved drum bottom. The improvement comprises a sloped channel through which the contents drains and collects in a depression. The depression accommodates a pump mechanism, the tube of which extends beneath the surface of the collected contents in the depression, thus allowing an increased amount of the drum contents to be removed from the container than previously possible. In addition, this improved drum bottom is of sufficient strength and rigidity to withstand the pressures commonly applied to drum bottoms.
II. Related Art
Bulgrin, U.S. Pat. No. 3,170,586, discloses a single walled metal container including a bottom end shell having a spherical domed surface. The bottom end shell implements an embossed sump extending from the center point radially outward and increases in size as it approaches the integral double walled chime. The Bulgrin Patent discloses a domed surface in conjunction with an integral double walled chime and sump configuration in order to provide the opportunity to use fittings for either the bottom or the side of the bottom end shell.
The primary object of the present invention is to drain the contents of the drum to a depression in the bottom of a container where a pump removes almost all of the contents. The present invention discloses a sloped surface, whereas Bulgrin shows a spherical domed surface. The contents of the Bulgrin container are under pressure in order to facilitate emptying, whereas the present invention employs a pump in the recess of the drum bottom for removal of the contents. While the present invention can contain pressurized contents, pressure is not a necessary element for removal of the contents.
Simon, U.S. Pat. No. 3,129,730, discloses a beer keg having a diametrically sloping depression in the bottom wall into which a discharge pipe of a pump extends to remove the contents. The Simon bottom head contains a diametrically sloped, centrally located depression, whereas the present drum bottom invention contains a sloped channel and a depression located several inches from the centerpoint. While the depression in the Simon bottom wall may collect some of the remaining contents of the container, it has a trough around the circumference of the bottom wall at a point lower than the diametrically sloping depression into which the discharge pipe of the pump extends. Therefore, a significant amount of liquid will collect in the trough rather than in the sump for removal by the pump. Although the present invention also has a trough at the outer rim, it retains only a few milliliters of contents. In addition, the drainage channel directs the flow of the contents past the central and rim sections for recovery of an increased amount over the Simon bottom head.
Bulgrin, U.S. Pat. No. 3,143,238, discloses a single wall metal container having a smooth concaved interior surface and a convexed exterior surface. The surfaces are bounded by an axially tapered annular flange. The center of the end shell contains a spherical embossment that projects axially outwardly of the exterior surface. The embossment provides for increased drainage from extending the tube into it. The entire bottom of the Bulgrin container is smooth and concave and contains a centrally located spherical embossment for collecting the remaining liquid. This Bulgrin container does not employ either the sloping channel, the sloping bottom or the off-center depression of the present invention.
The related art does not show the unique combination of the sloped channel and the depression of the present container bottom which is designed to provide for maximum removal of the container's contents. In fact, the present invention provides about a 2% or about a one gallon increase in the amount of drum contents that can be removed from a 55 gallon sized drum, or, about a 2.5% or a three-quarters gallon increase in the amount of drum contents that can be removed from a 30 gallon drum over the drum bottoms currently used in industry.